When Maggie Cunningham found a camera disguised as a cellphone charger in the bathroom at the Starbucks at 18 Wolf Rd. near Albany, New York, where she worked, she didn't know what to think.

"I was using the bathroom and ... [in the power outlet], I noticed what looked like an end of an iPhone charger, like a black cube," she told Inside Edition's Chief Investigative Correspondent Lisa Guerrero, showing her where she found the hidden camera.

"The way it's set up is that if this is plugged in here, the toilet is right there," Guerrero replied. "How incredibly disgusting."

Cunningham immediately took the device to her co-workers to examine it, in a moment that was caught on Starbucks' surveillance cameras. "I was jumping up and down once I found it was a camera," Cunningham said. "My co-workers and I have our jaws dropped, we can't believe that this is what we found."

She immediately called 911 to report it. "Hi, I'm calling from Starbucks," Cunningham tells the dispatcher in the call. "I work here and I was recently in the bathroom and I noticed a recording device plugged into the wall."

The Colonie Police Department obtained surveillance footage from the Starbucks in question and narrowed down their search to one specific customer, who was seen lurking around the bathroom. When they distributed his picture to local media, police said the tips began pouring in, including from the suspect himself.

His picture was distributed to local media, which pleaded for help identifying the man. Immediately, the tips began pouring in, police said, including from the suspect himself.

"He called us and said, 'That's me in the video I want to talk to you. I didn't do this,'" Lt. Robert Winn of the Colonie Police Department told Guerrero.

When he showed up at the station, the man, identified by police as Jonathan Waters, was questioned by detectives. As he was sitting for an interview, police obtained a search warrant and sifted through his garbage, where they hit pay dirt: a trove of hidden cameras embedded within ordinary items like key rings and phone chargers — like the one found at the Starbucks close to Albany.

"How surprised were you when you opened up that garbage can and found all these devices?" asked Guerrero.

When they went through the footage they saw the video of Cunningham finding the hidden camera at the Starbucks where she worked. They even saw Waters catching himself on his own hidden camera.

Police arrested Jonathan Waters, who was a customer, for secretly recording people. He pleaded guilty to unlawful surveillance and was sentenced one to three years in prison.

But Waters' case isn't an isolated incident. Inside Edition found that illegal hidden cameras have been discovered in 12 separate Starbucks bathrooms across the U.S. since 2011.

"It is getting more prolific nationwide just because of the ability to hide such small cameras in such normal-looking devices," Winn said.

Starbucks told Inside Edition: "Our partners (employees) take pride in creating a safe and welcoming environment for all, and are trained and equipped with resources to manage any potential security concerns in our stores. In this specific instance our partners acted quickly to remove the camera and loop in the appropriate authorities to ensure the safety and security of our customers and partners."

As for Cunningham, she's glad she called attention to the device when she did.

"I'm happy I found this camera before more people were caught on it and that it was put to an end," she said.